Having fun with science and technology.

Liberation Fonts Increase Document Interoperability

Ever wondered why a Word document you received looks garbled when
opening it in OpenOffice.org under GNU/Linux? Most likely, this is not
a bug in OOo's conversion algorithms, but a problem of missing
fonts. Most Word documents use fonts like "Arial" or "Times New
Roman", which are copyrighted by Microsoft. While Microsoft used to
distribute these so-called "core fonts" for non-Windows users, they
no longer do
so. There are
still places where you can get
them legally, but of course this
is not a free-as-in-speech solution. Therefore, these fonts are not
available by default in many GNU/Linux distros.

While the individual glyphs of a font can be copyrighted, their
metrics
(i.e., their spatial dimensions) cannot be, and therefore one can
create a free set of fonts that look different than their proprietary
counterparts, but otherwise behave the same when it comes to things
like linebreaking, hyphenation, etc. Red Hat has done just that, and
some time ago released the Liberation
fonts.

However, due to licensing issues not all major GNU/Linux distros
included the Liberation fonts. But after a long wait and the
persistent work by several people these issues have finally been
settled and the Liberation fonts have been accepted into the
Debian
archive. Other
distros are expected to follow suit soon.

When Red Hat released the Liberation fonts, they were distributed
under a
license
that was GPLv2 + two exceptions. The first exception posed no problem:
it simply states that embedding the fonts into a document does not
make the document a derivative work, a practice even the FSF
recommends
for fonts. The second exception, however, proved to be tricky. It
contains an anti-Tivoization clause requiring any physical
distribution to allow the installation of modified versions.

Now, while such a clause clearly does not make the fonts non-free, it
is a potential source of conflict with the GPLv2, as it forbids
imposing "any further restrictions" on the recipient. Even the
copyright holder is not exempt from this, as he could create an
invalid license, which means you cannot distribute the work at
all. When the Liberation fonts were initially proposed to be included
into Debian, they were
rejected
for this very reason, especially since Richard Stallman
objected
such a license in a similar situation.

Fortunately, this is not the end of the story. Red Hat's Tom
"spot" Callaway spoke to the FSF
and they
indicated
the license was fine according to them. When I came across this issue,
I asked the FSF once more, explicitly pointing them to RMS's point of
view. They
replied
that they definitely consider this license to be valid. And thanks to
the persistent work of Holger Levsen,
we finally managed to convince the Debian ftp-masters as well.

So let me use this opportunity to thank Tom, Holger and everyone else
involved in finally settling this issue.